Equation of a plane and distance from a point to that plane

Here's the problem:

"Consider the three points P = (1,7,3), Q = (5,9,2) and R = (2,6,5) that form a triangle.

a) Do these three points form the vertices of a triangle? If so, determine which point is the vertex of the right angle. (Use vector arithmetic and not the Pythagorean Theorem, to check if this is a right triangle.)

b) Find the equation of the plane that contains this triangle using a cross product calculation.

c) Find the distance from the point (2,2,0) to the plane that contains this triangle using a dot product calculation."

Right, right. So, for part C then, in order to find the distance from (2,2,0) to the plane that contains the triangle, I can use any of the points given to figure it out, right?

For example: (1,7,3) and (2,2,0) = (2-1)i+(2-7)j+(0-3)k = i-5j-3k or (1,-5,-3).
So then, it becomes (1,-5,-3) (dot product) (1,-3,-2)/sqrt(1^2+(-5)^2+(-3)^2), which is 32/sqrt(14), correct? And that's the distance to the plane?